Sony MZ-R91 Service Manual page 28

IC603 MPC18A20MTAEL
30 29 28 27
OP
1
2 3 4
IC605 XC6367B103MR
SLOW
START
REFERENCE
VOLTAGE
VDD
PHASE
COMPARATOR
VOUT 1
–
+
VDD 2
CHIP
CE
3
ENABLE
26 25 24 23
CHARGE PUMP
PRE DRIVER
COMP
+
CLK
SAW
VREF
PRE
COMP
DRIVER
6 8
5 7
VLX
LIMITER
PWM/PFM
BUFFER
CONTROL
OSC 100kHz
22 21 20 19 18
CLK
SAW
OSC
SAW
GEN
EFM
LOGIC
9 10 12
11 13
IC803 XC6383C301MR
CE 1
2
VOUT
5 EXT
NC 3
4 GND
IC902 RN5RG25AA-TR
GND
1
VDD
2
VOUT
3
– 44 –
17 16
CONTROL
LOGIC
EN ENB
BIAS
VREF
15
14
CHIP
ENABLE
VDD
VREF VLX LIMITER
BUFFER
+
2STEP PFM CONTROL
– OSC 100/180kHz
+
–
5
VREF
–
4
+
LX
5
4 VSS
CE
EXT